Fix localhost resolution

src/net.c

@@ -43,7 +43,7 @@ char *mg_ntoa(const struct mg_addr *addr, char *buf, size_t len) {
 }
 
 static bool mg_atonl(struct mg_str str, struct mg_addr *addr) {
-  if (mg_casecmp(str.ptr, "localhost") != 0) return false;
+  if (mg_vcasecmp(&str, "localhost") != 0) return false;
   addr->ip = mg_htonl(0x7f000001);
   addr->is_ip6 = false;
   return true;

src/net.h

@@ -3,6 +3,7 @@
 #include "arch.h"
 #include "event.h"
 #include "iobuf.h"
+#include "str.h"
 
 struct mg_dns {
   const char *url;          // DNS server URL